Using Storage as a Log

I'm trying to store info from gameplay into a log using storage. I'm having trouble finding a good way to do so.
Example of what I'm trying to do:
Say I have a server shop that you can sell items too, and I want to log every time a player sells something. Just for this example, I'll say there's only three things to track --gametime, amount of money received (reward), and the item type. 
Here's an example NBT output:
}
   Root:{
        Log:[
            {gametime:329598,item:"minecraft:diamond",reward:40},
            {gametime:329547,item:"minecraft:diamond",reward:10},
            {gametime:329262,item:"minecraft:diamond",reward:10}
        ],
        Pool:{
            gametime:329598,reward:40
        }
    }
}

Here is what code I have so far:
## POOL
execute store result storage se:telemetry Root.Pool.gametime int 1 run time query gametime
execute store result storage se:telemetry Root.Pool.reward int 1 run scoreboard players get $yield sell

## Update Log
# Prepend a template to the Log list. This is so every time this is run, there will always be a new template at index 0.
data modify storage se:telemetry Root.Log prepend value {gametime: -1, reward: -1, item: ""}
# Copy Pool.gametime into Log[0].gametime
data modify storage se:telemetry Root.Log[0].gametime set from storage se:telemetry Root.Pool.gametime
# Copy Pool.reward into Log[0].reward
data modify storage se:telemetry Root.Log[0].reward set from storage se:telemetry Root.Pool.reward
# Store item id. Pool value not needed because you can add directly from entity!
data modify storage se:telemetry Root.Log.[0].item set from entity @s SelectedItem.id

As you can see I am storing the values to a pool, and then storing them into the log. The log stores a new instance with new info every time a player sells something. 
The way I'm doing it works, but it seems a little over complicated.
Is there a better way to do this?